Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
  • C08B1/00—Preparatory treatment of cellulose for making derivatives thereof, e.g. pre-treatment, pre-soaking, activation
  • C08B1/003—Preparation of cellulose solutions, i.e. dopes, with different possible solvents, e.g. ionic liquids
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F2/00—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof
  • D01F2/02—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from solutions of cellulose in acids, bases or salts
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2301/00—Characterised by the use of cellulose, modified cellulose or cellulose derivatives

Definitions

• German Patent 72,572 for the production of such masses to employ asulphuric acid of 70 to 80 percent after the fibres has been previously treated with a sulphuric acid of 40 to 50 percent.
• E. Berl uses according to his German Patent 259,248 concentrations of sulphuric acid from 65 to 74 percent for dissolving cotton and wood cellulose.
• this characteristic range of concentration of sulphuric acid extends from 62.5 to 64 percent and, therefore, lies considerably lower than the hitherto prescribed values of concentration. Below this concentration range it is not possible to obtain a solution of the fibres. acid having a concentration lying below this characteristic range, the fibres become substantially only impregnated with sulphuric acid, whilst there is no swelling action and no dis- When using a sulphuric solving effect in the manner required formthe production of homogeneous masses. When-remploying a sulphuric acid having a concentration lying above 64 percent, the hydrolysis becomes already manifest as a disturbing action so that the use of this concentration requires the. observing of the known precautions necessary-for obtaining useful masses.
• the sulphuric acid having the specified low concentrations allows to avoid carrying out the solution at temperatures of below 10 centigrade which are prescribed as indispensablein the German Patent 259,248 of Berl. At this temperature, the fibres remain undissolved under. the conditions of the method of the invention even during several days.
• initial materials for the method according to the invention are useful bleached cotton linters as well as the bleached sulphate or soda cellulose prepared from wood. It is even possible to work with the cellulose in the form of board if they are pressed as little as possible on the paper manufacturingmachine so as to retain a loose structure and, thereby, to possess an advantageous capacity of absorbing the acid.
• As particularly useful has been proven a soda or sulphate cellulose decomposed by means of the sodium or sulphate process and which is improved by means of a subsequent alkaline tretament to such a degree that it shows a content of alpha cellulose exceeding percent and being preferably of 96 percent When transforming this tained qualities.
• the coagulation can be made to take place at normal or room temperature instead at temperatures not exceeding -10 centigrade, I
• Example 1 1 part of soda cellulose having a good absorbing capacity and being in the form of a board with'an alpha-cellulose content of 96 percent is mixed with 9 parts of sulphuric acid of 63.3 percent cooled to centigrade. The mixture is thoroughly kneaded in a kneading machine and in comparison with the processes hithertor with 8 parts of sulphuric acid or 62.8 percent as is left at rest during several hours. Then the mass is cooled down to about 7 centigrade during kneading until it is perfectly clear and capable of being spun into threads. The coagulation is carried out by pouring out the solution in the form of a thin layer and by introducing it into water at room temperature for the purpose of producing a foil.
• Example 2 1 part of cotton linters is mixedand treated described in connection with Example 1.
• a process for dissolving cellulose comprising initially treating cellulose with a sulphuric acid solution of a concentration of from 62.5% to 64% at a temperature of approximately 0 C. for a period of several hours.
• a process for dissolving cellulose comprising initially treating cellulose. with a sulphuric acid v solution of a concentration of from 62.5% to 64% at a temperature of 0 to --7 C. for a period of several hours.
• a process for dissolving cellulose comprising initially treating cellulose with a sulphuric acid solution of a concentration of from 62.5% to 64% at a temperature of approximately 0 C. for a period of several hours and thereafter reducin the temperature of the solution to approximately KURT HESS- 7 MAX ULMANN. RICHARD WEINGAND.,

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Organic Chemistry (AREA)
• Materials Engineering (AREA)
• Health & Medical Sciences (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Biochemistry (AREA)
• Life Sciences & Earth Sciences (AREA)
• General Chemical & Material Sciences (AREA)
• Textile Engineering (AREA)
• Artificial Filaments (AREA)
• Polysaccharides And Polysaccharide Derivatives (AREA)
• Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=6543604

Family Applications (1)

Country Status (4)

Families Citing this family (1)

• 0
  • NL NL47136D patent/NL47136C/xx active
• 1937
  • 1937-07-06 GB GB18811/37A patent/GB487365A/en not_active Expired
  • 1937-07-13 FR FR824320D patent/FR824320A/fr not_active Expired
  • 1937-07-13 US US153428A patent/US2293503A/en not_active Expired - Lifetime

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